<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <script src="./lib/jquery.js"></script>
</head>

<body>

<input type="file" id="file1"/>
<button id="btnUpload">上传文件</button>

<br/>
<img src="./images/loading.gif" alt="" style="display: none;" id="loading"/>

<script>
    $(function () {
        // 监听到Ajax请求被发起了
        $(document).ajaxStart(function () {
            $('#loading').show()
        })

        // 监听到 Ajax 完成的事件
        $(document).ajaxStop(function () {
            $('#loading').hide()
        })

        $('#btnUpload').on('click', function () {
            var files = $('#file1')[0].files
            if (files.length <= 0) {
                return alert('请选择文件后再上传！')
            }

            var fd = new FormData()
            fd.append('avatar', files[0])

            // 发起 jQuery 的 Ajax 请求，上传文件
            $.ajax({
                method: 'POST',
                url: 'http://www.liulongbin.top:3006/api/upload/avatar',
                data: fd,
                processData: false,
                contentType: false,
                success: function (res) {
                    console.log(res)
                }
            })
        })
    })
</script>

</body>

</html>
